Hello, Charles,
I am not familiar with the other sources you mention but I do have in my possession a rather detailed article Edith Russell penned for the Ladies Home Companion. I am going to be sending a copy of this piece to Phil Hind to use for ET. It contains 2 photos of Edith - one from about 1912, the other as she appeared around the time the article was published (1964). Though in small format, the article is ten pages in length.
To address your specific questions as to Edith's luggage,there are certainly indications that she had a very great deal of it - over and above what she would have been carrying for herself. She seems to have been unusually worried over it as well. There is no definite reference to her having an entire stateroom given over to her luggage but I will quote for you a few lines here and there from her narrative, from which you may deduce that the story of a separate cabin is not far-fetched:
"...I was a fashion writer, buyer, and stylist. This trip was one of the first of my career, as I had just started in business, and I was taking with me not only my own wardrobe but many orders executed for business firms and private clients. They were uninsured as when I applied for insurance on this merchandise, I was told that it was ridiculous to spend money for insurance when travelling on an unsinkable vessel..."
On boarding the Titanic from the tender at Cherbourg, Russell became fearful and informed White Star Paris bureau manager Nicholas Martin that she wanted to go back:
"...Mr. Martin said he would gladly release me from the sailing, if I felt that way, but he could not get my luggage off. "You are just nervous. You are perfectly safe..."
She obviously had much more than a few suitcases if they couldn't remove her luggage.
Later on, after the iceberg had been struck and she was waiting in the lounge, trying to decide to get on a lifeboat or not, she says she saw her steward Wareham and asked:
"...Wareham, what about my dresses and things? Do you think they will transfer my luggage?"
His reply: "If I were you, I think I would kiss them good-bye."
It was then that she begged him to go and fetch her lucky "mascot," that now famous toy pig.
As I say, there's not anything in this article to prove she was keeping things in another cabin but it would stand to reason that she could have been doing so if there was an empty one nearby. She surely had a lot of stuff with her.
By the way, though this may be known already, Edith Rosenbaum was the name she went by at the time she was on Titanic. Her articles for Women's Wear" (today "Women's Wear Daily") were always signed "EDITH L. ROSENBAUM." She took on the name "Russell" only in later years.
During my research on "Lucile," I have come across many "Women's Wear" fashion show reviews and other interviews with various rag-trade personalities by Rosenbaum so she is of special interest to me. I hope to find out more on her, as I feel she is deserving of more serious attention than she has been given in the past.
Hope this helps.
All my best,
Randy